Rate my team and need help to improve

[Einherjar9196]

This is my team need help to improve.
Glimmora @ Focus Sash
Ability: Toxic Debris
Tera Type: Rock
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Energy Ball
- Mortal Spin
- Power Gem
- Earth Power

Gliscor @ Toxic Orb
Ability: Poison Heal
Tera Type: Ground
EVs: 252 HP / 252 Def / 4 SpD
Impish Nature
- Earthquake
- Toxic
- Knock Off
- Protect

Salamence-Mega @ Salamencite
Ability: Aerilate
Tera Type: Dragon
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Dragon Dance
- Double-Edge
- Facade
- Roost

Gholdengo @ Air Balloon
Ability: Good as Gold
Tera Type: Steel
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Shadow Ball
- Make It Rain
- Power Gem
- Nasty Plot

Goodra-Hisui @ Assault Vest
Ability: Shell Armor
Tera Type: Steel
EVs: 252 HP / 252 SpA / 4 SpD
Quiet Nature
- Heavy Slam
- Draco Meteor
- Flamethrower
- Ice Beam

Kingambit @ Black Glasses
Ability: Supreme Overlord
Tera Type: Dark
EVs: 218 HP / 252 Atk / 38 Spe
Adamant Nature
- Swords Dance
- Sucker Punch
- Brick Break
- Iron Head